State Route 28 is an east–west state highway in the U.S. state of Ohio. Both of the route’s termini are on U.S. Route 50, beginning in Milford at the eastern terminus of State Route 126 and ending near Chillicothe. The route has an interchange with Interstate 275, and also intersects with U.S. Route 68 and U.S. Route 62. The route was formerly signed as State Route 27 before that number was assigned to U.S. Route 27 in 1926.

State Route 28 ran from Cincinnati to West Jefferson in 1924. This former alignment is occupied by U.S. Route 42 from Cincinnati to London, and State Route 142 from London to West Jefferson.

State Route 28 becomes a short controlled-access highway after the intersection with 275. Along the four lane expressway, which allows commuters to avoid the traffic associated with the shops along old 28, there are exits to North and South Wolfpen-Pleasant Hill Road on eastbound, but there are no exits westbound.